89xj slow electronics

My 89 xj seems to have very slow electronics and I'm not sure why? The power windows are slow, the pwr door locks dont quite have enough power to lock and unlock, the wipers are weak and slow, The power seats are slow, and finally the heater blower motor is weak and slow- I have replaced it and still slow. What could this be? I have upgraded to larger battery cables pos and negative, replaced the Ground from the engine to firewall, added a ground from battery to fenderwell, replaced the batt,to framerail to engine block ground and added one from the batt ground to the intake. As well as installed an optima battery. This sucks in the winter! dont care in the summer with half doors and I dont use the a/c

What is your static battery voltage measured between the terminals? What is your battery voltage measured between the terminals while running?